Just to refresh your memory, Rupert is the Snow White and the Hunstman director whom Kristen cheated on Rob with last summer.

"Rob was looking at her phone on the morning of his birthday, as he wanted to take a picture of something when she was in the shower," a source reveals.

"Suddenly, this message flashes up, and it’s not what he wanted to see," the insider continues. "He got straight up and left. Despite Kristen’s pleas, he told her not to come to his birthday party at a friend’s that night."

It appears that finding the text exchange was the final straw for Rob.

"He’s extremely angry and upset," says the source. "No matter how many times she calls or texts, friends say he’s had enough. After everything that happened and the hurt she caused, he’s furious she’d be back in touch with him, even if she is saying it’s completely innocent.”

Wow — crazy, right? If this is indeed true, we can't imagine why Kristen would want to have any contact with Rupert. Basically, we just want to give Rob a hug right now.